Low pressure flexible wall container



June 3, 1958 M. J.'GREBOWIEC 2,837,245

I LOW PRESSURE FLEXIBLE WALL CONTAINER Filed May 12, 1955 L INVENTOR. Z% ,9; M/bfiae/drefiow'ea BY Y I mro a4 tfi d States Paten Injection Molding Company, Kansas'City, Mo., a corporation of Application May 12, 1955, set-n1 No. 591,813

2 Claims. (Cl. 222184)- This invention relates'to relatively thin-walled, flexible or semi-rigid blown plastic containers and refers morespecifically to a flexible or semi-rigid blown plastic icontainer and base assembly for receiving, storing and dispensing sion such as insect sprays, shaving cream, etc.-

Heretofore, containers for products under .a compression of the order of and pounds per square inch have been made only of rigid materials."- 'Such'materials include metal, glass and some rigid 'plasticsJ, Addi-,

tionally, a container has been constructed of glass :coated with vinyl plastic to render it shatter-proof if broken. I

There area number of objectionablefeatureswto all of the materials above listed, varying','ofcourse, in relation to thespecific material. under l consideration.

Rigidity is not generally. a desirable factordn such product containers as it leads. to -breaka'ge or permanent distortion of the formof-thecontainer:.underzsuflicienteap plied force. have an objectionable weightvfactorizir; Some -.of .these materials are relatively. expensive compared to. the flex-- products under relatively low pressure compres- Additionally, most. of: the; above materials Many of'these materials ofler poor. decorativehave heretofore prevented their use in pressurized'containers. Thus, if the walls of the containerare made suthciently thin to have the desired resiliency,- there is a natural tendency of the container to bulge 'or balloon slightly under the applied compression pressure. This fact effectively prevents the employment of acon'cave :bo't tom such is generally required to provide a-stablebase.

Ifa concave bottom is formed in.-the -blown container' the compression pressure tends to force the bottom outwardly with concomitant excessive strain on the bottom edge. r I s Therefore, an object of the present invention is to provide a relatively thin walled, flexible .or semi-rigid blown plastic container for receiving, storing and dispensing products under relatively low pressure compression, said plastic container embodying-'the'above listed advantages and conveniences of containers of this sort while avoiding the disadvantages of weight, .rigidity, and aesthetic unfitness' as set forth for containers made only of rigid materials. 7 Another advantage of the present invention is to provide such a relatively thin walled, flexible or semi-rigid blown plastic container as set forth in combination; with a second plastic base forming segment whereby the bot- 2,837,245 Patented June 3, 1958 ice ' Fig. 1 is a side view of a preferred modification of a container embodying the invention.

Fig. 2-is a view taken along the in the direction of .the arrows.

Fig.3 is a view of the bottom of a container shown in Figs. 1 and .2.

' Fig. 4 is a side view with parts in section of a second modification of the invention.

1 Fig. 5 is a side view with parts in section of the lower portion of a container embodying a third modification of the invention.

Fig. 6 is a view of the bottom of is showntin either Fig. 4 or- 5. 1

In the drawings are shown three modifications of a container and base assembly," each embodying the invention. Figs. 1, 2 and 3 illustrate a preferred form and modification of the invention, while Figs. 4, 5 and 6 illustrate two additional modifications. The preferred modificationof Figswl, 2 and-3 will be described first.

Referring to Figs. 1, -2 and 3, the numeral 10 designates the sidewall of theone-piece body of a relatively thin walled, flexible or semi-rigid blown plastic con-. tainer of a type suitable for receiving, storing and dis-' pensing various products under relatively low pressure compression in the range of 15 to 20 pounds per square illChi It is contemplated that such a container might. have to withstand internal'pressures of up to 60 pounds per square inchunder certain conditions of temperature or external compression. No limitation is intended in the preceding statement other than to indicate the general contemplated pressure range of such a type of container. Any suitable plastic may be employed in the formation of such a blown container and, as an example, polyethylene is cited as an eminently suitable material possessing the required resiliency, blowing capabilities and strength. The neck portion of the container is indicated by 11 with thickened portion 12 for receiving the neck sealing construction. Any standard type, commercially produced spray or dispensing head 13 may be employed to seal the top of the coritainer. The structure and operation of such a sealinghead 13 is dependent upon the type of product contem plated for use in the container. As shown, the dis-' pensing head 13 may be roll-crimped over the container neck to produce an air-tight seal. a

Container 10 has a concave bottom 14 whereby to lines of Fig. l

a container such as minimine and prevent excessivebottom edge strain due to-pressurization of the contents of the container. Circumferential groove indent 15 is formed above the bottom edge in the wall 10 of the container. This indent is,' of course, formed in the original container blowing process.

Base piece 16 comprises a connected flange similar in cross-sectional shape to the cross-sectional shape of the container in the vicinity of indent 15. While only round containers are-shown in the drawings, it is not intended to limitthe disclosure-to such container forms and the-inventive structure embodied in the base piece 16.-container 10 combination is applicable also to irregularly shaped con-- i top diameter f said base piece 16 is equal to the outside diameter of the container wall 16 above indent 15.

Base piece 16-has inside circumferential bead 17 formedtherein below the top edgepf said base piece 16, said bead having a smallest inside diameter equal to the smallest outside diameterof the indent 15, whereby said base piece' lfi maybe readily snapped-on to the container to provide -'a levei stable base therefor.-- Base piece '16 has a length greater than the distance from the'indent to the wall of the container above the concave bottom is circum feren'tial trench-like indent iihaving't'o'pedge 24 and lower edge 25. The depth of'said'inden't is at all places either equal to or 'greater than the thickness of the base piece-whidhis to'be empioyed in'conjunction with this modificationof the container. The base piece or' support 26 comprises 'a conn'eetede'flange having a bottom "edge 26a and a top edge 26b. l l'ieinsidetliameter 'ofthetop edge of said-basepiecl'zli is equal to theiio'atside diameter ofthe top 24"-'ofindeiitmaria-aha outsidediameter *of= the top of base tpiece zfi is feqnalgt'o the'outside diameter of the" containerwall 19 irtirrretiiat'ely said indent. Base piece 26 has aii -"intfior subflange z h-extending' angularly downwardly and itiiegral i therewith. Subflan'ge 211's, "in oonjuntionwi'th the top portion'of said base piece 26, equal in length to the-length of said indent 23 and congruent in form '-therewith, whereby the reference to other features and subcombinations.

base piece *26may"be snap fitted=overthe'lower-portion erably,: the inside diame'ter' of the-lower'edge of said flange 211a equal tothe outside xiiam'eter of the lower edge'25 6f indent '23. It willbeseen that base piece 26 provides,in its fitted position'on the -container, a smooth with extension 'ofthe side of the container 19 in-contrast with the interrupted container walldo of the :preferred modification 'of Fig. l.

' Referring to the third modification of the invention shown in Fig. 5, the-wali of the container is indicated at 28 and-the concave bottom 29 is also illustrated. Circumferential indent 30 :is formed in the wall 28 of said container .abovelhebottom edge thereof and increase's regularly-in depth--downwar' dly to agcertain level and then decreases in depth 'at a' Ielatively'greater rate to form an essentiallftriangular trough'in the'side wall of the container. rBase pieceFSI'haVing' topedge '32 comprises a connected flange greater in length :than the distance from the top of the indent/to the lowest level of the concave bottom of the container, whereby to form, when posi-- tioned on said container, astable base "therefor. The top inside diameter of said basepiecei'al is equal to the outside diameter of the container above said indent. Base piece '31 hasfinterior subflange 33 extending angularly downwardly therefrom. Said subflange '33 is equal in length-to the length of the indent and congruent in form therewith, to permit said base piece to be snapped over said bottormo'f the container. The-inside diameter of the bottom edge of said subflange 33 is preferably equal to the least outside diameter of said indent 30. "It will be seen that top 32 interrupts the line of wntainer. i

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth together with, other advantages which-are obvious and which areinhe'rent to structure.

' It will 'be understood that'certain features "and sub a e-wanes of thecombinations are of utility and may be employed without It is contemplated by and is the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and notin a limiting sense.

Having thus described my invention, I claim:

'1. -Atw'o-pie'oe plastic container for relatively low pressuie' product storage comprising, in combinatioma sealable, plastic container with flexible walls of suflicient strength to receive relatively low pressure compression charges, the bottom' of'said container formed convex in cross section whereby to minimize pressurization strain on the bottom edge from said compression charges, a circumferential groove indent-formed in the side-surface of the container adjacent the bottom'thereof and a snap-on plastic base;piece adaptable to engage-the groove and fit about-said convex bottom of said container, the depth of the indent in'the wall of the container ranging from the thickness of the base piece material to a greater thickness, said base piece comprising an outer ring-shapedhflange having an inside top diameter-essentially equal to the outside diameter of the top portion ofthe groove indent and an ontside top diameter essentially equal to the outside diameter of :the container immediately above the groove indent therein, said .outer ring-shaped flange havingan interior subflange integral therewith and extending downwardly and inwardly therefrom, said subflange filling the portionof-the indent'not filled by the base piece proper and oongri1ent in fomi therewithwhereby said base piece may be snap fitted on said convex bottom container, the upper edge of thebase piece extending above said convex bottom of said-container and the bottom edge of said base piece extending' below said convex bottom of the con-- tainer to form a'stable resting base for-the container.

2. A two-piece plastic container for relatively low; pressure product storage comprising, in combination, a

scalable, plastic container wiih flexible walls of sufficient strength to receive relatively low pressure compression charges, the bottom of said container formed convex in cross section whereby to minimize pressurization strain on the bottom edge from said compression charges, a circumferential groove indent formed in the side surface of the container adjacent the bottom thereof and a snap-on plastic base piece adaptable to engage the groove and to fit about said convex bottom of said container, the groove indent in the walls of the container forming in cross section a taper-walled trough, said base piece comprising a ring-shaped hollow outer flange having a top inside diameter essentially equal to the outside diameter of the container immediately above said groove indent, and an interior subflange integral therewith extending inwardly angularly therefrom and integral therewith at one end, said subflange congruent in form with the upper side of said trough whereby said base piece may be snap fitted to said container, the upper edge of said base piece extending above said convex bottom of said container and the bottom edge of said base piece extending below said convex bottom of the container to form a stable'resting base for the container.

References Cited in the file of this patent UNITED STATES PATENTS 199,251 Baron et a1 Ian. 15, 1878 595,323 Lychenheim Dec. 14, 1897 2,294,858 Allen Sept. 1, 1942 2,363,474 Schlesinger Nov. 21, 1944 z,s7s,901 Tupper Dec. 18, 1951 2,673,661 Barton Mar. 30, 1954 FOREIGN PATENTS 771,150 'France Oct. 1, 1934 

